Derivative using direct definition of derivative 2-x/2+x

Which of the following situations represents a linear relationship? a. theresa increases the distance she runs by 0.1 miles every week. b. the volume of a box depends on the length of box. c. the amount of money in a bank account increases by 1 percent each year. d. the population of a town doubles every 5 years.

Write an algebraic expression for the word expression the quotient of c and 8

Ahiker stands at an unknown elevation before he ascends 2 miles up a mountain to an elevation of 9 miles. find the elevation of the hiker before his ascent.